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Spindle Turning How to sharpen and use roughing-down and coving gouges by Peter Chtld have only two shapes of blade. The roughing-down tool has a deep, U-shaped flute ground straight across with no pointed nose, and the coving gouge has a shallower flute with a pointed " lady's fingernail" nose. Roughing-down gouges have an even thickness of metal all F around the cutting edge and a very short single bevel of 45 ° . Unlike bowl gouges, they have no keel. Three sizes are commonly available: % in., 1 in. and 1 1/4 in. The first and last sizes should both be the choice of the turner if possible; the I-in. size is the economy combination tool. Caving (spindle) gouges have a longer bevel than roughing-down gouges. Four sizes will handle all the turner's requirements: Y4 in., larger coves, hollows or long curves can be done better with roughing-down gouges, so gouges larger than % in. aren't necessary. Both roughing-down and coving gouges should have long, heavy-duty handles to facilitate control-mine are at least 10 in. long. Gouges are cutting tools. They fashion a cove or hollow by % He was obviously misusing the gouge as a forming tool , pushing it straight into the revolving wood and scraping out a hollow which he required to be exactly % in. across. Using a 1%6 English master turner Peter Chtld, author a/The Craftsman Wood turner, wrote about turning bowls in the Winter '76 and Summer '77 issues a/Fine Woodworking. To start, lower gouge handle until cutting edge is just clear of stone. in. , "'h. cutting down from each side alternately until the desired shape is reached. A gouge is rarely the exact size of a desired cut. A customer of mine complained that a %-in. gouge supplied was in fact in. and consequently of no use to him. in. and % in. Any work requiring or turning between centers, standard roughing-down gouges and coving gouges are best. These spindle gouges gouge as a scraper is wrong. An important wood turning principle is that cutting tools always work from large diameter to small: Revolving wood cannot be properly cut "uphill. " This means that the tool must have room to work, especially at the bottom of the cove, so it is impossible to cut a %-in. cove with· a %-in. gouge. It would be better to use a "'h.-in. gouge. Most woodworking tools are properly shaped by the factory grinder and finisher, and sharpening is all that is needed before using them. Woodturning tools are an exception and have remained so, despite the efforts of professional turners to educate manufacturers. So be very critical regarding the shape and bevel length of brand-new gouge blades. You may find that a roughing-down gouge is not ground straight across, a condition which must be remedied on the grindstone. The bevel length will almost certainly be too long, not the correct angle of 45°. Sometimes a lot of metal (and money) has to be ground away before the correct angle is reached. As a temporary measure, a very short 45 ° angle can be ground on the longer bevel. This is against another basic wood turning principle, which is that no tool has more than one bevel on the cutting edge. Successive grindings, however, will eventually get down to one bevel of 45°. Do not try this dodge on new coving gouges. The grindstone is an important tool in the turner's shop and should be used not only as a "grind" stone but as a "sharpening" stone. The grit grade must not be so coarse that a sharp edge cannot be ground, or so fine that an edge can easily be burned at the tip. A good medium grit is a Carborundum (silicon carbide) dry wheel A54-N5-V30W or an equivalent grade. The diameter should not exceed 7 in. and the width should be at least 1 in. The stone should revolve towards the user at the fastest speed possible, although not To lower a handle the bevel slowly right angles to 60 the cutting side to side, gouge, hold the blade on the rest and tS just clear of the stone. Roll the point of contact at stone. As the bevel comes up (photo sequence), the bnght mark shows the operator for the jirst time where he tS removing metal. Lift or lower the handle untt! the center of the bevel IS reached, then continue to roll the blade with no vanation in hetght untt! the bevel starts to hollow out and fit the stone.